Advanced Photon Source

An Office of Science National User Facility

HYBRID code for beamline simulation

(a) HYBRID Flow chart; (b) Simulation of vertical beam intensity profilesThe project, in collaboration with Dr. Manuel Sanchez del Rio (ESRF), is to develop a fast and accurate code for simulating partially coherent radiation from synchrotron sources and its propagation through different optical elements. The HYBRID method uses geometric ray-tracing as its backbone and combines it with wavefront propagation within the framework of Fourier optics. The code computes diffraction effects when the beam is clipped by an aperture or by the finite size of the optics and can also simulate the effect of mirror figure errors when diffraction is present.  The far field version [(a) in image] of the code can be applied to an entire beamline by simulating each optical element iteratively, while the near field version is also available for investigating individual optics [(b) in image]. The partial coherence of the source is taken into account by numerical convolution and ray position/divergence re-sampling in order to improve the calculation efficiency. The HYBRID code has been benchmarked against the multi-electron version of SRW to show its validity in the case of fully, partially and non-coherent beams. The results demonstrate that the code is considerably faster than the multi-electron version of SRW and is therefore a useful tool for beamline design and optimization.

The HYBRID code uses SHADOW as the ray-tracing program for its popularity in the synchrotron radiation community. The wavefront propagation part uses the fast Fourier transform-based algorithm for its calculation speed. In general, the method used in the HYBRID code can be easily adapted to any ray-tracing program.

 

Distribution & Impact

Screenshots of the HYBRID input panel from (a) Igor and (b) SHADOWVUI The HYBRID code was initially developed using Igor Pro. The Igor version is also used as the master version for future improvement and is available upon request. The HYBRID code was also translated into IDL and implemented in SHADOWVUI (an XOP extension) as a macro. The latest version was distributed with SHADOWVUI in December 2014. The details of the code and its application can be found in the Publications section. Screenshots of the input panel from both versions are shown to the right

 

 

Funding Source

This project has been produced using APS Upgrade funding, as well as APS operational funding.

 

Please cite

For HYBRID: X. Shi, R. Reininger, M. Sanchez del Rio, L. Assoufid, “A hybrid method for X-ray optics simulation: combining geometric ray-tracing and wavefront propagation”, J. Synchrotron Rad. 21, 669 (2014). DOI:10.1107/S160057751400650X

For SHADOWVUI: X. Shi, M. Sanchez del Rio, R. Reininger, “A new SHADOW update: integrating diffraction effects into ray-tracing”, Proc. SPIE, 9209, 920911 (2014). DOI:10.1117/12.2061984

 

Related Publications

X. Shi, R. Reininger, M. Sanchez del Rio, J. Qian, L. Assoufid, “X-ray optics simulation and beamline design using a hybrid method: diffraction-limited focusing mirrors”, Proc. SPIE, 9209, 920909 (2014). DOI:10.1117/12.2061950

 

 

Immediate development goals include

  • Fast 2-D simulation
  • Simulating compound refractive lenses
  • Implementing a more accurate undulator source model
  • Simulating automatically the longitudinal evolution of the beam profile
 

Possible longer-term goals include

  • Evaluating the mutual coherence function of the beam
  • Implementing the HYBRID code into other ray-tracing codes
  • Developing standalone HYBRID package (no SHADOW dependency)